Manufacturers of security systems provide security devices for public and private institutions, commercial businesses, schools, hospitals and government institutions. The security devices are connected to security networks installed in the customer premises. Security systems that were once separate, such as systems for fire detection and suppression, video monitoring, and intrusion detection, are increasingly converging to form integrated or converged security systems connected to a common security network. This provides operators of security networks with improved management, reporting, problem isolation, and fault tolerance capabilities for the security devices in the security network.
Within a security network, security devices send messages to one another in communications protocols. Security devices typically include a combination of software protocol stacks and custom software that implement the communications protocols. The software protocol stacks are typically modeled after the OSI 7-layer model.
Converged security systems integrate many different security devices, or components, that communicate over the security network using standard and proprietary communications protocols. The components range in sophistication from simple sensor devices such as door sensors and access card readers that send one-way unsolicited messages in response to detected events, to more advanced devices such as fire alarm panels, video cameras and network video recorders. The latter devices typically support two-way communications and more flexible communications protocols, such as Internet Protocol (“IP”).
Moreover, security networks for converged security systems often include mixed installations of modern and legacy-based security devices. Security devices in modern security systems typically connect to shared bus network segments such as Ethernet, and utilize standard two-way IP protocols. Legacy-based systems, on the other hand, typically utilize a mix of standard and proprietary communications protocols on serial links or network segments.
A major challenge for manufacturers and system integrators of converged security systems is providing interoperability between security devices that support different communications protocols. The interoperability also has to take into account the fact that communicating security devices can reside on separate network segments with different physical layers, such as bus-based Ethernet and serial-based RS-232 links.
Additionally, security devices and the security network itself operate in a high-security environment. The security network is typically isolated from a company's data network. Operators and managers often have access only to those network segments within the security network that are within their immediate control and job function. This creates logistical and operational problems when coordinating and implementing software upgrades for security devices.
Current approaches to solving the problem of interoperability between security devices supporting different communications protocols include the use of custom software drivers, and a unifying protocol super-set. The custom driver approach requires that each security device provide a custom application programming interface (“API”), or server/driver, for each communications protocol that the security device does not currently support. The unifying protocol approach creates a single new protocol that provides interoperability between all security devices in the security network.